So, is this when you are just cruising or just trying to slowly accelerate, or when you are at 65 MPH and then punch it? If this is happening under cruise conditions then it won't be the secondaries; the engine will be running on the primaries at the point if cruising on flat land. And this is not the accelerator pump if this is at steady speeds.
Cruising at 60 doesn't use as much fuel as accelerating to 60 with your foot to the floor. I have a hard time believing it is a fuel delivery problem.
HaH I got you beat,I ran a 340 to valve float on a Carter 2bbl.
Got a chuckle out of that one.
Ok so an update. Spent the last day messing with the fuel system. Replaced the fuel pump, all hoses from the steel supply line coming forward from the tank all the way to the carb and the filter. It now will not idle for ****. I’ve taken the idle set screws all the way in and back out almost 3 turns and it still hasn’t leveled out. I’m not wanting to go any further than that because I’m not sure what that’s actually doing to the fuel delivery. I’ve looked at vacuum and now I’m at 16-17 and jumping all over instead of the smooth 20 I had before installing a brand new fuel pump.
I’m very new to carbs and timing so that’s why I had the carb professionally rebuilt a while back.
I will try and get the model number later today.
Dave, you said you had a 650. A 650 what? Although carbs all work basically the same, a 650 Holley and a 650 Carter/Edelbrock are way different.
Now that you changed something and got a negative result you need to go back to where you were or there is another issue to diagnose. If I were a betting man, I would say your new fuel pump is putting out too much pressure. You can either plumb in a temporary pressure gauge to diagnose or just throw a regulator at it and dial it to 4 or 5 pounds. Is there fuel dribbling out of the boost venturies onto the top of the closed throttle plates? It doesn't take much to cause what you are experiencing.
